Outcomes of early versus delayed initiation of extracorporeal life support in cardiac surgery

Postoperative hyper-inflammation as a predictor of poor outcomes in patients with acute type A aortic dissection (ATAAD) undergoing surgical repair

BACKGROUND

Postoperative hyper-inflammation is a frequent event in patients with acute Stanford type A aortic dissection (ATAAD) after surgical repair. This study's objective was to determine which inflammatory biomarkers could be used to make a better formula for identifying postoperative hyper-inflammation, and which risk factors were associated with hyper-inflammation.

METHODS

A total of 405 patients were enrolled in this study from October 1, 2020 to April 1, 2023. Of these patients, 124 exhibited poor outcomes. In order to investigate the optimal cut-off values for poor outcomes, logistic and receiver operating characteristic analyses were performed on the following parameters on the first postoperative day: procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6), and systemic immune-inflammation index (SII). These cut-off points were used to separate the patients into hyper-inflammatory (n = 52) and control (n = 353) groups. Finally, the logistic were used to find the risk factors of hyper-inflammatory.

RESULTS

PCT, CRP, IL-6, and SII were independent risk factors of poor outcomes in the multivariate logistic model. Cut-off points of these biomarkers were 2.18 ng/ml, 49.76 mg/L, 301.88 pg/ml, 2509.96 × 109/L respectively. These points were used to define postoperative hyper-inflammation (OR 2.97, 95% CI 1.35-6.53, P < 0.01). Cardiopulmonary bypass (CPB) > 180 min, and deep hypothermia circulatory arrest (DHCA) > 40 min were the independent risk factors for hyper-inflammation.

CONCLUSIONS

PCT > 2.18, CRP > 49.76, IL-6 > 301.88, and SII < 2509.96 could be used to define postoperative hyper-inflammation which increased mortality and morbidity in patients after ATAAD surgery. Based on these findings, we found that CPB > 180 min and DHCA > 40 min were separate risk factors for postoperative hyper-inflammation.

Should the Vasoactive Inotropic Score be a Determinant for Early Initiation of VA ECMO in Postcardiotomy Cardiogenic Shock?

OBJECTIVES

The authors investigated the role of early venoarterial extracorporeal membrane oxygenation (VA ECMO) implantation in patients with postcardiotomy cardiogenic shock (PCS) on mortality and morbidity when integrating vasoactive-inotropic score (VIS) and type of catecholamine support.

DESIGN

A retrospective, multicenter, observational study with propensity-weight matching.

SETTING

Four university-affiliated intensive care units.

PARTICIPANTS

Patients with PCS in the operating room.

INTERVENTIONS

Early VA ECMO support.

MEASUREMENTS AND MAIN RESULTS

Of 2,742 patients screened during the study period, 424 (16%) patients were treated with inotropic drugs, and 75 (3%) patients were supported by VA ECMO in the operating room. Patients supported by VA ECMO had a higher use of vasopressor and inotropic drugs, with a higher VIS score. After propensity matching (integrating VIS and catecholamines type), mortality (56% v 20%, p < 0.001) and morbidity (cardiac, renal, transfusion) were higher in patients supported by VA ECMO than in a matched control group.

CONCLUSIONS

When matching integrated the pre-ECMO VIS and the type of catecholamines, VA ECMO remained associated with high mortality and morbidity, suggesting that VIS alone should not be used as a main determinant of VA ECMO implantation.

Risk factors for postoperative myocardial injury-related cardiogenic shock in patients undergoing cardiac surgery

BACKGROUND

Myocardial injury-related cardiogenic shock (MICS) is significantly associated with poor outcomes in patients after cardiac surgery. Herein, we aimed to investigate the risk factor for postoperative MICS.

METHODS

We performed a case-control study on 792 patients undergoing cardiac surgery from 2016 to 2019, including 172 patients with postoperative MICS and 620 age- and sex-matched controls. MICS was defined as composite criteria: a cardiac index of < 2.2 L/m²/min, arterial lactate levels of > 5 mmol/L at the end of the surgery, a vasoactive-inotropic score of > 40 at the end of the surgery, and a cardiac troponin T (cTnT) level of > 0.8 µg/L on postoperative day 1 (POD1) with an increase of > 10% on POD 2.

RESULTS

A total of 4671 patients who underwent cardiac surgery in our hospital between 2016 and 2019 were included; of these, 172 (3.68%) had MICS and the remaining 4499 did not. For investigating the risk factors, we selected 620 age- and sex-matched controls. In the univariate analysis, MICS was significantly associated with death (P < 0.05), extracorporeal membrane oxygenation (P < 0.05), continuous renal replacement therapy (P < 0.01), and ventricular arrhythmias (P < 0.05). Multivariable logistic regression analysis revealed that diabetes mellitus (OR:8.11, 95% CI: 3.52-18.66, P < 0.05) and a cardiopulmonary bypass (CPB) time of > 2 h (OR: 3.16, 95% CI: 1.94-5.15, P < 0.05) were associated with postoperative MICS. Moreover, long-time administration of preoperative calcium channel blocker (CCB) was associated with a less incidence of MICS (OR: 0.11, 95% CI: 0.05-0.27, P < 0.05).

CONCLUSIONS

Postoperative MICS is significantly associated with poor outcomes. Diabetes mellitus and long CPB time are associated with MICS. Preoperative CCB administration is associated with less incidence of MICS.

Effect of venoarterial extracorporeal membrane oxygenation initiation timing on tricuspid valve surgery outcomes

Objectives

Tricuspid valve surgery is associated with high rates of shock and in-hospital mortality. Early initiation of venoarterial extracorporeal membrane oxygenation after surgery may provide right ventricular support and improve survival. We evaluated mortality in patients undergoing tricuspid valve surgery based on the timing of venoarterial extracorporeal membrane oxygenation.

Methods

All consecutive adult patients undergoing isolated or combined surgical tricuspid valve repair or replacement from 2010 to 2022 requiring venoarterial extracorporeal membrane oxygenation use were stratified by initiation in the operating room (Early) versus outside of the operating room (Late). Variables associated with in-hospital mortality were explored using logistic regression.

Results

There were 47 patients who required venoarterial extracorporeal membrane oxygenation: 31 Early and 16 Late. Mean age was 55.6 years (standard deviation, 16.8), 25 (54.3%) were in New York Heart Association class III/IV, 30 (60.8%) had left-sided valve disease, and 11 (23.4%) had undergone prior cardiac surgery. Median left ventricular ejection fraction was 60.0% (interquartile range, 45-65), right ventricular size was moderately to severely increased in 26 patients (60.5%), and right ventricular function was moderately to severely reduced in 24 patients (51.1%). Concomitant left-sided valve surgery was performed in 25 patients (53.2%). There were no differences in baseline characteristics or invasive measurements immediately before surgery between the Early and Late groups. Venoarterial extracorporeal membrane oxygenation was initiated 194 (23.0-840.0) minutes after cardiopulmonary bypass in the Late venoarterial extracorporeal membrane oxygenation group. In-hospital mortality was 35.5% (n = 11) in the Early group versus 68.8% (n = 11) in the Late group (P = .037). Late venoarterial extracorporeal membrane oxygenation was associated with in-hospital mortality (odds ratio, 4.00; 1.10-14.50; P = .035).

Conclusions

Early postoperative initiation of venoarterial extracorporeal membrane oxygenation after tricuspid valve surgery in high-risk patients may be associated with improvement in postoperative hemodynamics and in-hospital mortality.

An Intensivist-Led Extracorporeal Membrane Oxygenation Program: Design, Implementation, and Outcomes of the First Five Years

We describe the development, implementation, and outcomes of an intensivist-led adult extracorporeal life support (ECLS) program using intensivists both to perform venovenous (V-V), venoarterial (V-A), and extracorporeal cardiopulmonary resuscitation (ECPR) cannulations, and to manage patients on ECLS throughout their ICU course. All adults supported with ECLS at the University of New Mexico Hospital (UNMH) from February 1, 2017 to December 31, 2021 were retrospectively analyzed. A total of 203 ECLS cannulations were performed in 198 patients, including 116 V-A cannulations (including 65 during ECPR) and 87 V-V cannulations (including 38 in patients with COVID-19). UNMH intensivists performed 195 cannulations, with 9 cannulation complications. Cardiothoracic surgeons performed 8 cannulations. Overall survival to hospital discharge or transfer was 46.5%. Survival was 32.3% in the ECPR group and 56% in the non-ECPR V-A group. In the V-V cohort, survival was 66.7% in the COVID-19-negative patients and 34.2% in the COVID-19-positive patients. This large series of intensivist-performed ECLS cannulations-including V-A, V-V, and ECPR modalities-demonstrates the successful implementation of a comprehensive intensivist-led ECLS program. With outcomes comparable to those in the literature, our program serves as a model for the initiation and development of ECLS programs in settings with limited access to local subspecialty cardiothoracic surgical services.

A new machine learning algorithm to predict veno-arterial ECMO implantation after post-cardiotomy low cardiac output syndrome

BACKGROUND

Post-cardiotomy low cardiac output syndrome (PC-LCOS) is a life-threatening complication after cardiac surgery involving a cardiopulmonary bypass (CPB). Mechanical circulatory support with veno-arterial membrane oxygenation (VA-ECMO) may be necessary in the case of refractory shock. The objective of the study was to develop a machine-learning algorithm to predict the need for VA-ECMO implantation in patients with PC-LCOS.

PATIENTS AND METHODS

Patients were included in the study with moderate to severe PC-LCOS (defined by a vasoactive inotropic score (VIS) > 10 with clinical or biological markers of impaired organ perfusion or need for mechanical circulatory support after cardiac surgery) from two university hospitals in Paris, France. The Deep Super Learner, an ensemble machine learning algorithm, was trained to predict VA-ECMO implantation using features readily available at the end of a CPB. Feature importance was estimated using Shapley values.

RESULTS

Between January 2016 and December 2019, 285 patients were included in the development dataset and 190 patients in the external validation dataset. The primary outcome, the need for VA-ECMO implantation, occurred respectively, in 16% (n = 46) and 10% (n = 19) in the development and the external validation datasets. The Deep Super Learner algorithm achieved a 0.863 (0.793-0.928) ROC AUC to predict the primary outcome in the external validation dataset. The most important features were the first postoperative arterial lactate value, intraoperative VIS, the absence of angiotensin-converting enzyme treatment, body mass index, and EuroSCORE II.

CONCLUSIONS

We developed an explainable ensemble machine learning algorithm that could help clinicians predict the risk of deterioration and the need for VA-ECMO implantation in moderate to severe PC-LCOS patients.

Applications and Outcomes of Extracorporeal Life Support Use in Adult Liver Transplantation: A Case Series and Review of Literature

The use of extracorporeal life support (ECLS) is increasingly reported in adult liver transplantation (LT). However, neither the role of ECLS in the perioperative setting for LT nor its outcomes has been well defined. We performed a retrospective chart review of all adult LT patients at our institution who received ECLS from 2004 to 2021. We also conducted a comprehensive literature search for adult LT cases that involved perioperative ECLS for respiratory or cardiac failure. Over the study period, 11 LT patients required ECLS at our institution, two for respiratory and nine for cardiac failure. Both patients with respiratory failure received ECLS as a bridge to LT and survived to discharge. Nine patients required ECLS for acute cardiac failure either intraoperatively or postoperatively, and two survived to discharge. In the literature, we identified 35 cases of respiratory failure in LT patients requiring perioperative ECLS. Applications included preoperative bridge to LT (n = 6) and postoperative rescue (n = 29), for which overall survival was 44%. We identified 31 cases of cardiac failure in LT patients requiring either ECLS or cardiopulmonary bypass for cardiac support or rescue for intraoperative or postoperative cardiac failure (n = 30). There is evidence for consideration of ECLS as a bridge to LT in patients with potentially reversible respiratory failure or as rescue therapy for respiratory failure in posttransplant patients. ECLS has a prohibitively high risk of futility in pretransplant patients with cardiac failure but may have a role in LT patients with a functioning graft and potentially reversible cardiac failure.

Vasoactive-Inotropic Score as a Determinant of Timely Initiation of Venoarterial Extracorporeal Membrane Oxygenation in Patients With Cardiogenic Shock

BACKGROUND

The predictive role of the vasoactive-inotropic score (VIS) for clinical outcomes after venoarterial extracorporeal membrane oxygenation (VA-ECMO) in patients with cardiogenic shock is not well known. This study investigated the predictive value of VIS on in-hospital outcomes and the determination of optimal timing for the initiation of VA-ECMO.

METHODS AND RESULTS

Overall, 160 patients with cardiogenic shock requiring VA-ECMO who were treated between December 2012 and August 2018 were analyzed. The in-hospital outcomes according to VIS were compared. Pre-ECMO VIS had an area under the receiver-operating characteristic curve (AUC) of 0.60 (P=0.03) for the prediction of in-hospital death. When the patients were divided into the high (≥32) and low (<32) VIS groups, the high VIS group had a higher rate of in-hospital death (P=0.002) and a lower rate of ECMO weaning (P=0.004). The difference in in-hospital death according to VIS was significant only in patients with a cardiogenic shock of non-ischemic etiology (P=0.01). Extracorporeal cardiopulmonary resuscitation (hazard ratio [HR], 1.99), age (HR, 1.02), pre-ECMO lactate (HR, 1.06), and VIS ≥32 (HR, 2.46) were independently predictive of in-hospital death.

CONCLUSIONS

Among patients with cardiogenic shock requiring VA-ECMO, the initiation of VA-ECMO before reaching high VIS (≥32) showed better in-hospital outcomes, suggesting that VIS may be a potential marker for determining the initiation of hemodynamic support with VA-ECMO.

Venoarterial Extracorporeal Membrane Oxygenation for Postcardiotomy Shock-Analysis of the Extracorporeal Life Support Organization Registry

OBJECTIVES

Refractory postcardiotomy cardiogenic shock complicating cardiac surgery yields nearly 100% mortality when untreated. Use of venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock has increased worldwide recently. The aim of the current analysis was to outline the trends in use, changing patient profiles, and in-hospital outcomes including complications in patients undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock.

DESIGN

Analysis of extracorporeal life support organization registry from January 2010 to December 2018.

SETTING

Multicenter worldwide registry.

PATIENTS

Seven-thousand one-hundred eighty-five patients supported with venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock.

INTERVENTIONS

Venoarterial extracorporeal membrane oxygenation.

MEASUREMENTS AND MAIN RESULTS

Hospital death, weaning from extracorporeal membrane oxygenation, hospital complications. Mortality predictors were assessed by multivariable logistic regression. Propensity score matching was performed for comparison of peripheral and central cannulation for extracorporeal membrane oxygenation. A significant trend toward more extracorporeal membrane oxygenation use in recent years (coefficient, 0.009; p < 0.001) was found. Mean age was 56.3 ± 14.9 years and significantly increased over time (coefficient, 0.513; p < 0.001). Most commonly, venoarterial extracorporeal membrane oxygenation was instituted after coronary artery bypass surgery (26.8%) and valvular surgery (25.6%), followed by heart transplantation (20.7%). Overall, successful extracorporeal membrane oxygenation weaning was possible in 4,520 cases (56.4%), and survival to hospital discharge was achieved in 41.7% of cases. In-hospital mortality rates remained constant over time (coefficient, -8.775; p = 0.682), whereas complication rates were significantly reduced (coefficient, -0.009; p = 0.003). Higher mortality was observed after coronary artery bypass surgery (65.4%), combined coronary artery bypass surgery with valve (68.4%), and aortic (69.6%) procedures than other indications. Lower mortality rates were observed in heart transplantation recipients (46.0%). Age (p < 0.001), central cannulation (p < 0.001), and occurrence of complications while on extracorporeal membrane oxygenation were independently associated with poorer prognosis.

CONCLUSIONS

The analysis confirmed increased use of venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock. Mortality rates remained relatively constant over time despite a decrease in complications, in the setting of supporting older patients.

Basics of extra corporeal membrane oxygenation: a pediatric intensivist's perspective

Extra Corporeal membrane oxygenation (ECMO) is one of the most advanced forms of life support therapy in the Intensive Care Unit. It relies on the principle where an external artificial circuit carries venous blood from the patient to a gas exchange device (oxygenator) within which blood becomes enriched with oxygen and has carbon dioxide removed. The blood is then returned to the patient via a central vein or an artery. The goal of ECMO is to provide a physiologic milieu for recovery in refractory cardiac/respiratory failure. The technology is not a definitive treatment for a disease, but provides valuable time for the body to recover. In that way it can be compared to a bridge, where patients are initiated on ECMO as a bridge to recovery, bridge to decision making, bridge to transplant or bridge to diagnosis. The use of this modality in children is not backed by a lot of randomized controlled trials, but the use has increased dramatically in our country in last 10 years. This article is not intended to provide an in-depth overview of ECMO, but outlines the basic principles that a pediatric intensive care physician should know in order to manage a kid on ECMO support.

Case Report of Fulminant Eosinophilic Myocarditis With Concomitant Pheochromocytoma

A 33-year-old woman presented with fulminant eosinophilic myocarditis requiring venoarterial extracorporeal membrane oxygenation (ECMO). A computed tomography (CT) scan revealed a retroperitoneal mass that was eventually diagnosed as a pheochromocytoma. This case highlights the need for a comprehensive diagnostic workup for acute cardiomyopathy manifesting as cardiogenic shock in young patients and the benefit of early initiation of mechanical support facilitating both diagnosis and recovery.

Mechanical circulatory support in paediatric population

Extra-corporeal membrane oxygenation is a life-saving modality to support the cardiac and/or pulmonary system as a form of life support in resuscitation, post-cardiotomy, as a bridge to cardiac transplantation and in respiratory failure. Its use in the paediatric and neonatal population has proven incredibly useful. However, extra-corporeal membrane oxygenation is also associated with a greater rate of mortality and complications, particularly in those with co-morbidities. As a result, interventions such as ventricular assist devices have been trialled in these patients. In this review, we provide a comprehensive analysis of the current literature on extra-corporeal membrane oxygenation for cardiac support in the paediatric and neonatal population. We evaluate its effectiveness in comparison to other forms of mechanical circulatory support and focus on areas for future development.

Clinical characteristics and outcomes of adults with peripheral extracorporeal membrane oxygenation in a developing country: A single center 8-year retrospective study

INTRODUCTION

In our institute, we began using peripheral veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) in 2010, and peripheral veno-venous (VV) ECMO in 2015. This study aimed to describe clinical characteristics and outcomes in those patients.

METHODS

We reviewed retrospective data of adults receiving peripheral ECMO from January 2010 to December 2017 and divided it into two groups for analysis: VA- and VV-ECMO.

RESULTS

There were 28 patients in the VA group and 12 in VV. For VA, the mean (SD) age was 58.5 (17.2) years. The most common indication was cardiac arrest (12 patients, 42.9%); 15 patients (53.6%) were on intra-aortic balloon pump concomitantly. In the VV cohort, the mean age was 53.3 (16.2) years. Eleven (91.7%) patients had acute respiratory distress syndrome as an indication. The mortality rate of VA-ECMO was 85.7%, and VV was 58.3%.

CONCLUSION

The mortality rate in our ECMO center was considerably higher than that in the international registry report. Improved team education, rigid patient selection criteria, and a reimbursement protocol should lead to ameliorated outcomes.

TRIAL REGISTRATION

TCTR20190120001. Registered January 19, 2019.

Extracorporeal Life Support in Postcardiotomy Cardiogenic Shock: A View on Scenario, Outcome, and Risk Factors in 261 Patients

BACKGROUND

Weaning failure from cardiopulmonary bypass, postoperative low cardiac output (LCO), and cardiopulmonary resuscitation (CPR) are common scenarios preceding extracorporeal life support (ECLS) implantation after cardiac surgery. The impact of these scenarios on short- and long-term outcome are not well described.

METHODS

Between March 2006 and December 2018, 261 patients received ECLS support after cardiac surgery. Data of patients with weaning failure (NW), postoperative LCO, and CPR leading to ECLS implantation were retrospectively analyzed regarding outcome. Risk factors for outcome after postcardiotomy ECLS were assessed by uni- or multivariate regression analysis.

RESULTS

Median duration of extracorporeal support was 5.5 ± 8.5 days. Overall mortality on ECLS was 39.1%. Scenario analysis revealed weaning failure from cardiopulmonary bypass in 40.6%, postoperative LCO in 24.5%, and postoperative CPR in 34.9% leading to initiation of ECLS. Most common cause of death was refractory LCO (25.3%). Overall follow-up survival was 23.7%. Survival after weaning and during follow-up in all subgroups was 9.2% (CPR), 5.0% (LCO), and 9.6% (NW), respectively. Uni- or multivariate regression analysis revealed age, aortic surgery, and vasopressor medication level on day 1 as risk for death on support, as well as postoperative renal failure, and body mass index (BMI) as risk factors for death during follow-up.

CONCLUSION

Mortality after postcardiotomy ECLS is high. Overall, outcome after CPR, NW, weaning failure and LCO is comparable. Postoperative resuscitation does not negatively affect outcome after postcardiotomy ECLS. Neurological status of ECLS survivors is good.

Heparin-binding protein measurement improves the prediction of myocardial injury-related cardiogenic shock

Background

Heparin-binding protein (HBP), a potent inducer of increased vascular permeability, is a potentially useful biomarker for predicting outcomes in patients with postoperative myocardial injury-related cardiogenic shock (MIRCS). We aimed to evaluate and validate HBP as a prognostic biomarker for postoperative MIRCS.

Methods

We performed a case-control study in 792 patients undergoing cardiac surgery from January 1, 2016, to August 1, 2019, including 172 patients with postoperative MIRCS and 620 age- and sex-matched controls. The association between HBP and MIRCS was determined by multivariate logistic regression analysis. Receiver operating characteristic curves (ROCs) with area under the curve (AUC) were performed to calculate the cut-off value, sensitivity and specificity. The association between HBP and cardiac troponin T (cTnT) was determined by multivariable linear regression analysis. Blood samples were drawn from the coronary sinus and arterial line of the cardiopulmonary bypass (CPB) before aortic cross-clamping (time point 1) and 5 min after aortic declamping (time point 2).

Results

Before aortic cross-clamping, coronary sinus HBP (HBP_CS1) showed no differences between the two groups. However, after declamping, the MIRCS group had a significantly higher sinus HBP level (HBP_CS2) than did the control group. HBP_CS2 predicted MIRCS with an AUC of 0.85 (95% CI: 0.81–0.89, cut-off: 220 ng/ml, sensitivity: 92% and specificity: 70%). After adjusting for confounding factors, we found that HBP was an independent risk factor for MIRCS (OR: 7.65, 95% CI: 4.86–12.06, P < 0.01) and was positively associated with cTnT (β > 0, P < 0.01).

Conclusions

Elevated levels of coronary sinus HBP were useful biomarkers for predicting MIRCS after cardiac surgery.